In certain programs aimed to sell goods (so-called television shopping), the viewer's will to purchase goods can be communicated to a server through a telephone network or the like up link. In this sort of the program, services can be rendered by embedding the ancillary information necessary in purchasing the commodities, inclusive of the telephone number for connection to the server in making an offer for purchase, in a gap of the analog broadcast waves. However, with the currently operating broadcast system, it is not possible to supply a sufficient amount of the information to the viewer because of constraint in e.g., the signaling system. However, in the digital broadcast system, as used in the next-generation broadcast system, in which an appreciably large quantity of the information can be transmitted, there is a good prospect for realization of variegated services employing the program ancillary data. For example, there is a good prospect for realization not only of an interpolating service of checking for a singer's profile as the song program on air is viewed, but also of a bidirectional service of placing an order for commodities presented on a display picture as a picture program on air is viewed.
However, even if the amount of the information acquired is increased, but the access to the required information is not facilitated, it is not possible to render attractive services for the viewer.